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61.
During the second half of the 20th century, the Ganga River ecosystem has been continuously altered by several ongoing anthropogenic processes, accommodating multi-dimensional pressure due to increase of nearly four-fold human population. For solution of any environmental issues of the river, the Earth System Science approach is required to have maximum socio-economic benefits to millions of people living in Indian and Bangladesh. A bibliography containing more than 250 references on environmental studies of the Ganga River was prepared to preserve its ecosystem by providing the baseline support in this regard.  相似文献   
62.
ABSTRACT

The aim of this work is to provide a systematic approach for sustainability criteria clustering into different useful categories. For this purpose, a methodology has been proposed with the following three steps. (i) A comprehensive set of the sustainability criteria in economic, environmental and social dimension has been extracted from the literature and have been customised for the iron and steel industry. (ii) A fuzzy Kano methodology has been used to classify these sustainability criteria into useful Kano cluster like must-be, one-dimensional, and attractive cluster (iii) further, must-be and attractive criteria derived from the second step were further sub-classified into three categories using Type IV Kano model. All steps have been examined in the iron and steel industry of India and findings indicate that quality and delivery criteria are classified as high must be criteria in the economic realm. Further, environmental and energy management system in the environmental dimension and social responsibility and right of stakeholders criteria in the social dimension are classified as high must be criteria. Prioritising must be and attractive criteria enable decision makers of other industries to select the appropriate criteria to adopt sustainability.  相似文献   
63.
Thraustochytrid protists characteristically accumulate high amounts of lipids, much of which is comprised of the polyunsaturated fatty acid, docosahexaenoic acid (DHA). Since DHA is important in human health, thraustochytrids have attracted much attention from the point of view of biotechnology. However, the biological rationale of DHA production in the storage lipids of these organisms is not clear. We carried out three experiments to study this. (1) The fate of lipids in thraustochytrids during development was studied by staining lipids of vegetative cells with the fluorescent vital stain for lipids, namely Nile blue, following the growth of the cells. The fluorescent lipid bodies decreased in abundance in freshly formed motile limaciform amoeboid cells and subsequently disappeared when they moved away. When vegetative cells produced vast extensions of plasma membrane, the ectoplasmic net elements (EN), the fluorescent lipids appeared to be transported to them. (2) Changes in lipids and DHA during starvation were examined in cells with enhanced lipid and DHA contents and those in which they were not enhanced. Cells in which lipids and DHA were enhanced by refrigerating them for 48 h survived starvation for a longer period. Compared to cells that had not been refrigerated, total fatty acids, as well as DHA were marginally higher in pre-refrigerated cells, while palmitic acid levels were lower. Starvation of cells resulted in a gradual decrease of absolute concentrations and percentage levels of DHA after 8 days, while percentage of palmitic acid levels increased. (3) The relationship between DHA and specific gravity of cells was studied by comparing cells pre-refrigerated as above with those which were not pre-refrigerated. Refrigerated cells with increased lipids and DHA showed higher specific gravities than non-refrigerated cells. We suggest the following roles for storage lipids and DHA in thraustochytrids: (1) lipids serve as energy sources during movement of cells and for production of EN; (2) DHA in storage lipids become distributed in the plasma membrane when EN are formed; (3) DHA is preferably utilized as a fatty acid energy reserve during starvation and (4) an unknown mechanism results in negative buoyancy of cells when total lipids and DHA are marginally enhanced. DHA in storage lipids might be crucial to the survival of thraustochytrid cells.  相似文献   
64.
Light microscopic and ultra-structural studies of the lymphoid tissues such as blood immunocytes, spleen and pronephros of the freshwater catfish, Clarias batrachus, were carried out. The peripheral blood showed nucleated erythrocytes, total leucocytic count (TLC) more than that observed in mammalian blood and leucocytes with morphological appearance similar to the mammalian white blood cells (WBCs). The spleen and pronephros showed presence of numerous lymphocytes, monocytes and nucleated red blood cells (RBCs) along with hemosiderin-containing macrophages. The morphology of lymphoid organs of the catfish has been discussed in light of the evolution of the immune system in this class of vertebrates.  相似文献   
65.
The results of a study designed to quantify the levels of PCDD/Fs in boiler and control device ashes resulting from burning sludge of bleached mill origin, admixed with bark, are summarized.  相似文献   
66.
Laboratory studies were undertaken to evaluate the persistence of alpha-endosulphan, beta-endosulphan and endosulphan sulphate in four diverse soils under non-flooded and flooded conditions. Significant variations were observed in the extent of persistence of the three chemicals in different non-flooded soils with maximum persistence observed in Alfisol and the least in Mollisol having near neutral pH and higher organic matter. Degradation was more in all the flooded soils than in the non-flooded counterpart but in Vertisol under flooded and non-flooded conditions, the rate of degradation of endosulphan sulphate was found to be nearly same.  相似文献   
67.
In today’s world of stricter drinking water disinfection standards there is a search for disinfection solutions that abide by the new standards while keeping the disinfection operation cost-efficient and safe. Ozone disinfection has the potential not only to meet but also to exceed the limits. Along with disinfection, the use of ozone for drinking water treatment can also have many other benefits such as taste and color removal, iron and manganese removal, and insecticide removal. p]Ozone disinfection has been used widely in Europe for well over a century, but many of its great benefits are just now being realized in the United States. Ozone disinfection has been the focus of many recent studies in the drinking water field. p]The purpose of the research for this paper was to analyze ozone disinfection from technology transfer and related policy perspectives. This paper reports the aspects used to analyze the technology as well as the results. A modified version of the Strategic Technology Evaluation Program was used to evaluate ozone disinfection’s transfer viability. p]This study has demonstrated that ozone disinfection, to be fully accepted into the drinking water industry, must first be accepted by the American Water Works Association, a nationally recognized professional and trade organization. Once this acceptance is gained, individual municipalities will more readily accept the technology. p]Another driving force that will likely bring about the adoption of ozone disinfection of drinking water would be stricter drinking water disinfection standards that can be best met by this technology.  相似文献   
68.
Globally, yam (Dioscorea spp.) is the fifth most important root crop after sweet potatoes (Ipomoea batatas L.) and the second most important crop in Africa in terms of production after cassava (Manihot esculenta L.) and has long been vital to food security in sub-Saharan Africa (SSA). Climate change is expected to have its most severe impact on crops in food insecure regions, yet very little is known about impact of climate change on yam productivity. Therefore, we try estimating the effect of climate change on the yam (variety: Florido) yield and evaluating different adaptation strategies to mitigate its effect. Three regional climate models REgional MOdel (REMO), Swedish Meteorological and Hydrological Institute Regional Climate Model (SMHIRCA), and Hadley Regional Model (HADRM3P) were coupled to a crop growth simulation model namely Environmental Policy Integrated Climate (EPIC) version 3060 to simulate current and future yam yields in the Upper Ouémé basin (Benin Republic). For the future, substantial yield decreases were estimated varying according to the climate scenario. We explored the advantages of specific adaptation strategies suggesting that changing sowing date may be ineffective in counteracting adverse climatic effects. Late maturing cultivars could be effective in offsetting the adverse impacts. Whereas, by coupling irrigation and fertilizer application with late maturing cultivars, highest increase in the yam productivity could be realized which accounted up to 49 % depending upon the projection of the scenarios analyzed.  相似文献   
69.
Disposal and beneficial-use options for street sweeping residuals collected as part of routine roadway maintenance activities in Florida, USA, were assessed by characterizing approximately 200 samples collected from 20 municipalities. Total concentrations (mg/kg or μg/kg) and leachable concentrations (mg/L or μg/L) of 11 metals and a number of organic pollutant groups (volatile organics, semi-volatile organics, pesticides, herbicides, carbamates) in the samples were measured. The synthetic precipitation leaching procedure (SPLP) was performed to evaluate the leachability of the pollutants. From the total metal analysis, several metals (e.g., arsenic, barium, chromium, copper, nickel, lead, and zinc) were commonly found above their detection limits. Zinc was found to have the highest mean concentration of all metals measured (46.7 mg/kg), followed by copper (10.7 mg/kg) and barium (10.5 mg/kg). The metal with the smallest mean concentration was arsenic (0.48 mg/kg). A small fraction of the total arsenic, barium, lead, and zinc leached in some samples using the SPLP; leached concentrations were relatively low. A few organic compounds (e.g., 4,4′-DDT, endrin, and endosulfan II) were detected in a limited number of samples. When the total and leaching results were compared to risk-based Florida soil cleanup target levels and groundwater cleanup target levels, the street sweepings were not found to pose a significant human-health risk via direct exposure or groundwater contamination.  相似文献   
70.
The marine environment is continuously subjected to chemical pollution, which may exert a detrimental effect on aquatic organisms. Biodiversity of marine invertebrates has been proven to be difficult to assess accurately using traditional morphological methods. Major problems include dearth of characters in many taxa. Hence, it is necessary to assess the eco-health of this marine invertebrate using reliable measurements of environmental quality as required in the present study. With the backdrop of information, the Pudhumadam coastal area was surveyed for the diversity of ruined/washed out gastropods species. As a competitor for space with gastropods, these barnacles settle on the conus for its food and habitat. In our study, the occurrence of acorn barnacles was observed on gastropod shells. The pink adult and many white small barnacles were noted on the shells. If these barnacles increase their habitat this may lead to destruction of diversity of gastropods.  相似文献   
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